Lumbar disc herniation is a syndrome caused by degeneration, rupture, protrusion, irritation or compression of the spinal cord or nerve roots, and is one of the most common causes of back and leg pain. I. Overview (a) Etiology 1. degeneration Degeneration of the intervertebral disc is the basic factor of the disc. With age, the water content of the annulus fibrosus and nucleus pulposus gradually decreases, the tension and elasticity of the nucleus pulposus decreases, and the disc structure relaxes, with changes more pronounced in the posterior lateral aspect of the annulus fibrosus, which is not supported by the posterior longitudinal ligament.2. Injury Accumulated injury is the main cause of disc degeneration. Also, injury is a common causative factor for lumbar disc herniation. 3. occupation People with a history of long-term bending and lumbar torsion work are susceptible to lumbar disc herniation, such as drivers and students. 4. genetics The incidence of the disease is reported to be lower in people of color. 5. pregnancy The relative relaxation of various tissue structures in the pelvis and lower back during pregnancy, along with increased weight bearing, can easily cause disc damage. (2) Pathological types 1. bulging type The fibrous ring is partially ruptured, but the superficial layer is intact, when the nucleus pulposus is confined to the spinal canal due to pressure, but the superficial layer is smooth. The nucleus pulposus protrudes into the spinal canal with only the posterior longitudinal ligament or a layer of fibrous membrane covering it, and the surface is uneven or cauliflower-shaped. 3. prolapse type ruptured and protruding disc tissue or fragmented into the spinal canal or completely free. II. Rehabilitation assessment (a) Clinical manifestations are common in young and middle-aged people, more men than women, with a history of bending work or sitting work, and the first onset is often in the process of half-bending and holding weight or suddenly making twisting movements. 1. Low back pain is the earliest symptom, mostly deep swelling pain, extending from the midline of the spine to both sides, accompanied by unilateral lower limb radiating pain, also seen bilaterally. The pain is aggravated by increased abdominal pressure such as coughing and deep breathing. 2. gait and posture In mild cases, there is no significant change, while in more severe cases, the gait is restrained and walking is slow, often accompanied by intermittent claudication, and there may be scoliosis deformity. The majority of lower lumbar disc herniations are associated with sciatica, with typical sciatica radiating from the lower lumbar region to the buttocks, posterior thighs, lateral calves, and into the feet. 4. compression of the cauda equina nerve A herniated nucleus pulposus or prolapsed or free disc tissue may compress the cauda equina nerve, resulting in bowel and urinary disorders and abnormal sensation in the saddle area. A small number of patients have numbness and swelling of the limbs. (II) Signs 1. change in spinal physiological curvature and scoliosis is a postural compensatory deformity formed by the passive position taken by the patient to relieve pain. The more common ones are lumbar physiological flexion straightening and lumbar scoliosis. When the protrusion is lateral to the nerve root, the lumbar scoliosis is more convex to the affected side, while when the protrusion is medial to the nerve root, the lumbar scoliosis is convex to the healthy side. Intermittent claudication, also known as painful claudication, is characterized by a small step of the affected limb, often landing on the tip of the foot and rapidly changing to the healthy foot after landing (the support phase is short and the swing phase is long), resulting in a rapid and unstable gait. 3. limited lumbar movement The movement of the lumbar region will stretch the compressed nerve roots and cause pain, most obviously in the forward flexion position. 4. Lumbar pressure pain and sacrospinous muscle spasm There is a lot of pressure pain in the area of the spinous process gap, supraspinous and interspinous ligaments, and paraspinous area of the diseased vertebral space, as well as pressure pain on the affected nerve trunks or branches, such as the buttocks, N fossa, and the posterior aspect of the calf. At the same time, 1/3 of patients have spasm of sacrospinous muscle, which makes the patient’s low back fixed in forced position. 5. sensory abnormalities When there is nerve root involvement, patients mostly have sensory abnormalities, and the area of sensory abnormalities corresponds to the involved nerve root. 6. decreased muscle strength More than 70% of patients showed decreased muscle strength, see Table 1 for the correspondence. Table 1: Comparison table of lumbar nerve injury and decreased muscle strength No. Involved nerve roots Dominant muscles Motor function 1 L1, L2, L3 Iliopsoas muscle Hip flexion 2 Obturator nerve (L2 to 4) Short retractor, long retractor, large retractor Hip internal retraction 3 Femoral nerve (L2 to 4) Quadriceps muscle Knee extension 4 Sciatic nerve ( L4~5) Anterior tibialis, extensor digitorum longus, extensor digitorum longus Foot inversion, dorsiflexion5 Superior gluteal nerve (L4~5, S1) Gluteus medius, gluteus minimus Hip abduction7. Reflex abnormalities Weak or absent knee reflex indicates different degrees of injury to L4 nerve root; weak or absent ankle reflex indicates S1 nerve root compression; when there is cauda equina nerve compression, there is weak or absent anal reflex. (iii) Special examination 1. straight leg elevation test The straight leg elevation test is a valuable test for the diagnosis of lumbar disc herniation. Its sensitivity of diagnosing lumbar disc herniation is 76%~97%. (1) Examination method The patient lies supine with both legs straight and the affected limb is passively elevated. (2) Positive judgment Normal people do not experience discomfort in the N fossa until the lower extremity is elevated to 60° to 70°, so the presence of sciatica within 60° of elevation is considered positive. (3) Caution The effect of N cord muscle contracture and other factors should be excluded, and the height should be increased appropriately for athletes or patients with a history of long-term pulling of the N cord muscle or indicated. This test is only performed if the straight leg raise test is positive. (1) Test method When the straight leg raise test is positive, slowly lower the height of the affected limb, wait until the radiating pain disappears, and then passively flex the ankle joint. (2) Positive judgment If sciatica reappears, it is positive, otherwise it is negative. (3) Caution: Same as straight leg raise test. The patient lies prone, flexes the affected knee joint, the examiner fixes the pelvis with one hand, holds the distal calf of the affected side with the other hand, and passively externally rotates the calf or allows the patient to resist internal rotation of the calf. (2) Positive judgment The presence of sciatica is positive, otherwise it is negative. (3) Caution: Take care to fix the pelvis and knee joint to prevent displacement. The patient is lying prone with the lower limb straight. The examiner fixes the patient’s pelvis with one hand, holds the patient’s lower leg with the other hand, and pulls the patient forward for hip extension. (2) Positive judgment The presence of radiating pain in the front of the thigh is positive, otherwise it is negative. (3) Caution: Pay attention to fixing the pelvis. 5. The patient lies on his back and the examiner bends his neck forward so that the lower jaw is close to the chest. (2) Positive judgment If there is involuntary hip flexion, knee flexion or lumbar leg pain, it is positive. (3) Precautions: Ask the patient to relax the whole body. （X-ray is the most commonly used and economical imaging method, which can not only provide a basis for the diagnosis of lumbar disc herniation, but also differentiate it from certain diseases with the same symptoms of low back pain, such as bone tumor, ankylosing spondylitis, spondylolisthesis and spondylolisthesis. (1) Radiographic position: Generally, frontal and lateral examinations are performed, and if necessary, oblique or functional positions (such as hyperflexion and hyperextension) can be performed. (2) Plain film signs of lumbar disc herniation include: (1) the physiological anterior lumbar convexity becomes shallow or disappears, or even reverse convexity, and there may be lumbar lateral convexity at the same time; (2) the lesioned vertebral space becomes narrower, equal width anteriorly and posteriorly, and the left and right gaps are not equal; (3) there may be sclerosis and lip-like hyperplasia at the edge of the lesioned vertebral space. 2. CT electron computed tomography (CT) can directly show the location, size, shape and relationship with the surrounding structures of the herniated disc. (1) Scanning conditions and methods: the general window position of intervertebral disc scan is 80-100Hu and the window width is 450-600Hu. (2) The common CT signs of lumbar disc herniation are as follows: ① block shadow, mostly formed by the disc beyond the vertebral body edge; ② calcification, mostly seen at the posterior edge of the vertebral body; ③ free fragmentation, mostly herniated nucleus pulposus shadow; ④ epidural sac compression, deformation and displacement; ⑤ epidural fat deformation and disappearance; ⑥ nerve root compression (6) nerve root compression, displacement, and enlargement; (7) enlargement of the lateral saphenous fossa; (8) Schmorl’s node, which is a single or multiple bone defect of similar density to the intervertebral disc in the middle or posterior 1/3 of the upper or lower edge of the vertebral body, surrounded by an osteosclerotic zone of varying width. 3. MRI Magnetic resonance imaging (MRI) has higher resolution of soft tissues and no bone artifacts, and is mostly used for the diagnosis of cranial, spinal, spinal cord, and joint lesions. (1) Imaging type MRI imaging is mainly divided into T1-weighted image (TE) and T2-weighted image (TR). Generally, intervertebral discs show slightly low signal in T1-weighted images and high signal in T2-weighted images. When the disc undergoes dehydration degeneration, the signal decreases and is more pronounced on T2-weighted images. (2) MRI can clearly distinguish the different stages and types of disc herniation. (1) bulging disc: the high-signal nucleus pulposus does not protrude beyond the low-signal fibrous annulus; (2) herniated disc: the high-signal nucleus pulposus protrudes beyond the low-signal fibrous annulus, but its protruding part is still connected to the parent nucleus pulposus; (3) prolapsed disc: the high-signal nucleus pulposus protrudes beyond the low-signal fibrous annulus, but its protruding part is not connected to the parent nucleus pulposus. (4) Other tests, such as myelography, epidurography and discography, are rarely used in clinical practice. (V) Other tests Laboratory tests are of little significance for the diagnosis of lumbar disc herniation itself, but can be used for differential diagnosis; electrophysiological tests, such as electromyography, can also assist in determining the extent and degree of nerve damage. III. Basis of rehabilitation treatment 1. anti-inflammatory and analgesic Early physical therapy can improve local blood circulation of the injury, promote dissipation of inflammation, loosen adhesions and reduce pain. 2. Promote protrusion retraction Through traction, manipulation and other treatments, it can promote the retraction of the protrusion or improve the structural relationship between the protrusion and its surrounding tissues. At the same time, local muscle and tendon strength training can also make the protrusion retract, and have the effect of preventing the continued development of the lesion. Bed rest can reduce inflammation and avoid aggravation of injury. Generally, absolute bed rest should not exceed 1 week. After the improvement of symptoms, some simple activities of daily living should be carried out as far as possible. At the same time, attention should be paid to maintain the correct posture or movement of activities, and the waist brace can be worn during activities. (ii) Medication medication can eliminate inflammation and improve symptoms, and the commonly used medications are as follows. 1. non-steroidal anti-inflammatory and analgesic drugs (NSAIDs): more commonly used anti-inflammatory and analgesic drugs, the main mechanism is to inhibit the synthesis and release of prostaglandins. Side effects such as gastrointestinal reactions are obvious. COX2 selective inhibitors that have emerged in recent years have relatively small adverse effects. 2. muscle relaxants: loosen local muscle tissue to achieve anti-inflammatory and analgesic effects. 3. adjuvant analgesics: including antidepressants, antispasmodics, anticonvulsants, etc. These drugs can enhance the analgesic effect when used in combination with NSAIDs. 4. narcotic analgesics: they are mostly used to relieve acute pain and are generally not preferred. 5. Chinese herbal medicine: many Chinese herbal medicines have certain efficacy in anti-inflammatory and analgesic aspects. In the acute phase of lumbar disc herniation, edema at the spinal nerve root cuff is more pronounced, which is not only one of the main causes of severe pain, but can also lead to secondary arachnoid adhesions. In order to eliminate the local reactive edema, intravenous steroids, diuretics such as dihydrocortisone, and dehydrating agents such as mannitol can be administered intravenously under pressure (c) Traction It has been reported that traction can reduce the intradiscal pressure, nerve root irritation and compression symptoms. Traction can be divided into continuous traction and three-dimensional traction, and continuous pelvic traction is currently the most common clinical practice. Traction weight is generally between 7 and 15 kg, twice a day for 1 to 2 hours, for 2 weeks to 3 months. It is contraindicated in pregnant women and patients with severe cardiovascular disease. Patients with lumbar disc herniation with CT or MRI examination suggesting lumbar disc bulge without complete rupture, lateral saphenous fossa stenosis not exceeding 2/3 of the original, disc herniation extruding spinal canal not exceeding 1/2 of the original volume or spinal canal anterior-posterior diameter not less than 0.8 cm, left-right diameter not less than 1.0 cm, location of the herniated disc calcification not located in the lateral saphenous fossa, no obvious osteoporosis or hyperplasia bypass, slippage and having severe Patients with heart disease are eligible for this approach. Central disc herniation with saddle area numbness and incontinence; lumbar disc herniation with obvious nerve damage, such as weakened lower limb muscles, drooping feet, loss of bunion dorsiflexion or plantar flexion muscles; disc herniation with spinal stenosis or bony stenosis of the spinal canal, with anterior and posterior canal diameters less than 0.6 cm and right and left diameters less than 0.75 cm, and walking no more than 500 meters; ruptured disc herniation with complete loss of the lateral saphenous fossa, and a spinal canal volume less than 1/3 of the original volume. The volume of the spinal canal is less than 1/2 or the anterior-posterior diameter is less than 0.8 cm, the left-right diameter is less than 1.0 cm, the ruptured fragment is free in the spinal canal causing compression, the herniated disc of the lateral type (neurogenic foramen type) directly compresses the nerve root foramen, and the herniated disc calcifies and stenoses the lateral saphenous fossa without significant improvement of symptoms after 3 weeks of conservative treatment or recurrence without obvious causes within 1 year; after 6 weeks of treatment in the first and second stages (d) Physiotherapy The effects of physiotherapy are analgesic, anti-inflammatory, neuromuscular excitation and release of adhesions. Short-wave and ultrashort-wave therapy: At the initial stage of the disease, in order to improve the blood circulation of the affected area, eliminate the possible inflammatory reactions such as exudation and edema, and reduce the pain caused by compression or stimulation of nerve roots (e) Traditional manipulation Tui na can make the protrusion retract, change the relationship between the protrusion and the surrounding tissues, and reduce inflammation and analgesia. Generally, for the first attack, those with a disease duration of less than 3 months, or those with mild symptoms and signs, or those who cannot tolerate surgery, acupressure treatment has clear effects; however, acupressure is not suitable for those with large protrusions, severe adhesions between protrusions and nerve roots, severe stenosis of the spinal canal, lumbar spondylolisthesis, lateral saphenous fossa stenosis, and those with spinal bone lesions. Acupuncture also has clear efficacy in anti-inflammation and analgesia. (vi) Injection therapy Sacral fissure injection block therapy is commonly used, that is, the drug is injected into the epidural cavity through the sacral fissure, and the drug travels up the spinal canal to the affected nerve root to reduce local inflammation and adhesions. Generally, corticosteroid solution is mostly used, once a week, 3 times as a course of treatment. Suitable for people with significant pain and poor results of general treatment. Local regional closure: can be divided into superficial and deep closure: 1, superficial closure: the scope of closure includes the lumbar dorsal fascia, lumbar muscle starting and ending points and the supraspinous ligament, interspinous ligament. It is generally required to combine pressure pain points and precise anatomical sites. (vii) Exercise training The role of exercise training is to maintain the normal spine shape of the patient, improve the strength of the lumbar back muscles and enhance the elasticity of the ligaments around the vertebral body. 1. acute period Within 1 week, bed rest is the main focus, and the lower limbs can be appropriately padded to reduce spinal stress. 2. In the remission period, gradually start lumbar and abdominal muscle training, paying attention to avoid overflexion or hyperextension of the lumbar vertebrae. 2 to 3 sets per day, 10 to 15 times per set, lasting 5 to 10 seconds each time. (1) Half-bridge training: supine position, with head and feet as support points, making the hips lift off the bed. Insufficient strength can also be supplemented by two-handed support. (2) back flying training: prone position, with the abdomen as the support point, the upper limbs behind the back, the chest and both lower limbs lift off the bed at the same time, shaped like a flying swallow, also known as the “flying swallow”. (3) posterior extension training: prone position, both lower limbs naturally straight, alternately lifting upward as far as possible.